<!DOCTYPE html>
<html lang="zh">
<head>
    <meta charset="UTF-8">
    <title>宽度自适应模式</title>
    <link rel="stylesheet" href="css/normalize.css">
    <link rel="stylesheet" href="layout3.css">
</head>
<body>
<div class="wrapper">
    <div class="header"><h1>宽度自适应设计-左中右模式</h1></div>
    <div class="main">
        <div class="left-side"><p>定宽250px</p></div>
        <div class="right-side"><p>定宽250px</p></div>
        <div class="content"><p>内容区域自适应宽度</p></div>
    </div>
    <div class="footer"><address>页脚</address></div>
</div>
</body>
</html>